Effect of Suture Size and Type on Bone Cutout in Transosseous Tendon Repairs

Purpose: We compared bone cutout of polyester and polyblend suture in 2 suture sizes with static and cyclic loading in a Sawbone model (Pacific Research Laboratories, Vashon, WA). Methods: Polyester and polyblend sutures in both No. 2 and No. 5 sizes were placed through transosseous tunnels in closed-cell polyurethane foam and tied over the bar of an electromechanical load frame at a fixed height. Seven sutures in each group were pulled at a rate of 1 mm/s until bone cutout occurred. Another set of 28 sutures were cyclically loaded at increasing loads until failure. Results: With static and cyclic loads, No. 5 polyester suture (Ethibond; Ethicon, Somerville, NJ) and No. 5 polyblend suture (FiberWire; Arthrex, Naples, FL) had a higher cutout load than the No. 2 sutures (P < .001). No. 2 polyblend suture had a higher static failure load than No. 2 polyester suture (P = .02). With cyclic loading, No. 2 polyblend suture had a higher load to cutout than No. 2 polyester suture (P = .01), and No. 5 polyblend suture had a higher load to cutout than No. 5 polyester suture (P = .003). Conclusions: No. 2 sutures showed bone cutout at lower forces under static and cyclic loading as compared with No. 5 sutures in this Sawbone model, and no decrease in performance with regard to bone cutout was noted with polyblend as compared with polyester. Clinical Relevance: No. 5 polyester or polyblend suture may be preferable to No. 2 suture to avoid bone cutout in tendon-to-bone repair, and No. 5 polyblend may be preferable to No. 5 polyester to avoid bone cutout.